1. Field of the Invention
The present invention relates to a sealing structure for sealing between a periphery of a sliding roof and an opening portion of a roof panel of a motor vehicle and, more particularly, to a sealing structure for a tiltable sliding roof of a motor vehicle.
2. Description of Related Art
As shown in FIG. 1, a sliding roof 10 is provided to open and close a roof opening formed in a roof panel 12 of a motor vehicle. To close the roof opening, the sliding roof 10 is slid frontward, and to open the roof opening, the sliding roof 10 is slid rearward (Publication of unexamined patent application No. 2000-335255, ex.).
To prevent intrusion of rainwater, etc. into a vehicle compartment, as shown in FIG. 2, a roof panel seal 14 is attached to a periphery of the sliding roof 10 so as to seal a gap between an opening portion 16 of the roof panel 12 and the sliding roof 10.
The roof panel seal 14 includes a base portion 18 to be attached to the sliding roof 10, and a tubular portion 20 integrally formed with the base portion 18. The roof panel seal 14 is composed of rubber or thermoplastic elastomer. To attach the roof panel seal 14, the base portion 18 is fitted on a moulding 22 provided along the periphery of the sliding roof 10.
When the sliding roof 10 is closed, the tubular portion 20 pushes and seals a vertical wall of the roof panel 12. The tubular portion 20 may not always push the vertical wall constantly due to the variation of the sliding conditions of the sliding roof 10 or the assembling conditions of a vehicle body. If the pushing force of the tubular portion 20 is small, rainwater, etc. may intrude inside the sliding roof 10 through a gap between the tubular portion 20 and the vertical wall of the roof panel 12.
Rainwater, etc. intruded flows along the tubular portion 20 and drops into a drip channel 24 provided under the opening portion of the roof panel 12 (Publication of unexamined patent application No. Hei 9-207580, ex.). For providing the drip channel 24, a space is needed, thereby increasing the thickness of the roof of the motor vehicle.
To open and close the roof opening of the roof panel 12, the sliding roof 10 is tilted up or down. For ensuring the tilting operation of the sliding roof 10, the drip channel 24 must be spaced from the sliding roof 10 so that it has been difficult to make the roof compact.
While the sliding roof 10 is repeatedly tilted up and down, the tubular portion 20 of the roof panel seal 14 rubs the vertical wall of the roof panel 12 to cause wear thereof. And the tubular portion 20 moves vertically with the titling operation of the sliding roof 10 to cause the scattering in the contacting state of the tubular portion 20 and the facing vertical wall of the roof panel 12, thereby decreasing the sealing properties of the tubular portion 20.
To overcome this problem, it has been tried to attach a roof panel seal to the opening portion 16 of the roof panel 12 so as to contact a lower surface of the periphery of the sliding roof 10 in a closed state. To cover the periphery of the rectangular sliding roof 10 entirely, the roof panel seal must be formed into a four-sided configuration, and to effect sufficient sealing properties, the roof panel seal must be attached to the opening portion 16 securely. Accordingly, the roof panel seal has been attached to the opening portion 16 with clips and double-sided adhesive tapes.
Normally, the double-sided adhesive tape has a long straight configuration. When the long and straight double-sided adhesive tape is bonded to the roof panel seal having a four-sided configuration, it must be bent in conformity with corners of the roof panel seal. Upon bending, the double-sided adhesive tape wrinkles to produce irregularities after bonded, which may deteriorate the bonding properties. The double-sided adhesive tapes exhibit flexibility and are easy to stretch. Consequently, upon bonding, ends of the double-sided adhesive tapes may stretch and overlap each other, thereby deteriorating the bonding properties and the sealing properties of the double-sided adhesive tapes.
Furthermore, it has been demanded to increase the opening area of the roof panel 12 for brightening a vehicle compartment, enabling good flowing of air, improving the relaxing feeling and obtaining a good view.
Where the sliding roof 10 is composed of a single sliding panel, it must be slid by a long distance to open and close the roof opening, thereby enlarging the driving mechanism for the sliding roof 10, and deteriorating the designing properties thereof. And when the sliding roof 10 is slid rearward, it may project rearwardly of the vehicle body.
Under the above circumstances, it has been also tried to compose the sliding roof 10 of a plurality of sliding panels which are arranged longitudinally of the vehicle body. With this arrangement, however, sealing is needed between adjacent sliding panels.
To effect sealing between adjacent sliding panels, weather strips are respectively attached to facing surfaces thereof (Publication of unexamined utility model application No. Hei 7-35142, ex.).
To attach the weather strips to the adjacent sliding panels, respectively, it takes much trouble and time, and accordingly, production costs increase.
In addition, the weather strips may not always contact the facing surfaces properly, because of the variation of the assembling state of the plurality of sliding panels and the deformation of the weather strips attached to the sliding panels.
Furthermore, the weather strip may have a tubular seal portion for improving the sealing properties. The tubular seal portion, however, has the problem that when the sliding roof is opened, a seal wall of the tubular seal portion may remain closely contact with a base portion of the weather strip without returning to its original protruded configuration. In addition, the seal wall of the tubular seal portion may generate noise when leaving the base portion of the weather strip.